


One Day

by vermilionvice



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Angst, Biting, Crimson Flower, F/M, Marking, Oral Sex, Porn With Plot, Riding, Smut, Teasing
Language: English
Status: In-Progress
Published: 2020-07-27
Updated: 2020-07-27
Packaged: 2021-03-06 00:40:12
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,637
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25544512
Author URL: https://archiveofourown.org/users/vermilionvice/pseuds/vermilionvice
Summary: Set after their A Support, Dorothea invites Sylvain to her room before he gets a chance to invite her to dinner. In the midst of their war waged alongside Edelgard, they find solace in the promise of one day together, even if that one day cannot be today.***Sylvain/Dorothea smut with a little plot, there will be a second part set after the events of Crimson Flower. This is unedited but enjoy!
Relationships: Dorothea Arnault/Sylvain Jose Gautier
Comments: 5
Kudos: 12





	One Day

“Though… I’d much rather win you over now, and be with you until you’re an old grandma.” Sylvain confessed earnestly, surprising Dorothea and making warmth bloom in her chest.

It was the most genuine thing she’d ever heard him say. She’d known him over six years, trust her, she’d suffered enough of his bullshitting. This…. wasn’t that. 

They flirted back and forth over the years, made out a few times in shrouded corners of the monastery, he told her she was perfect and gorgeous and she whispered how strong he was and how much she liked his hands on her. It worked for them, a constant source of attention when they needed it but pushed to the wayside when their eyes wandered elsewhere.

Each individually assumed it worked best for the other person, right? Dorothea could smell Sylvain’s true disdain for the girls who approached him, which is why he flirted first. It made it seem like he was in charge, he initiated it not them. His choice to be used and his choice to dump her when he got bored. 

Dorothea wasn’t sure if she was capable of loving anyone, not after all she’d been through, but if someone happened to fall in love with her…. well, that was good enough, right? Basically the same thing? Dorothea supposed it would do, as long as she was taken care of in the end. Not everyone got a happy ending, and if the happiest she could achieve was to avoid starving in the streets after her female beauty expiration date came to pass… so be it. 

But those words from Sylvain, they were… closer to an, ‘I love you,’ than even when he said those three words verbatim. The words slid over her skin, made her shiver a little. Someone who wanted to grow old with her, not just love her when she was young and beautiful.

She smiled softly at him and felt herself meander a big closer, her skirts brushing his legs as she gazed up at him, “That might be legitimately the most romantic thing you’ve ever said Sylvain.” Dorothea couldn’t help but tease him a little, and his crooked grin made her glad she did. 

Suddenly nervous, feeling a little exposed as she felt a rush of affection for the man in front of her. Huh. “That’s new,” she lied to herself internally. 

It wasn’t new at all, just it started as a seed that grew over the years. Despite his irritating habits and disingenuous speeches, Dorothea always had a soft spot for him. She couldn’t say she was displeased when he elected to join the Black Eagles, she liked having him in class. He was funny. 

And, she could sense, somewhat of a kindred spirit. Not just a flirt. After their mission involving his brother Miklan, when she understood better the poison of Crests in Sylvain’s life, was probably the moment Dorothea first realized she cared for him. But it was too dangerous to have feelings for the resident player. 

And now here he was, telling her with the most determined look in his eyes that he wanted to win her over now. He wanted to marry her and be with her, become parents and grandparents. 

But it had been promised to Dorothea before, and taken away. Men will say anything to convince you to open up to them. 

However, her true feelings rushed forth before she had a moment to stuff them back in. It was a mix of their proximity, the look in his eyes, and the smell of him, leather, sweat, Sylvain, that was muddling her mind.

“I can’t say I disagree…. I’d rather you win me over now, too, so I can stay by your side until you’re an old grandpa.” That was the best, ‘I love you,’ that Dorothea could yet muster. She knew Sylvain understood, he leaned closer and her eyes fluttered. 

“You’re blushing…” he murmured, his hand coming up to tuck her hair behind her ear. Now her heart was pounding, he knew exactly how to get her like this. They’d never gotten past a little bit of petting, but it’s not as though either of them hadn’t thought about it. By the time they were realizing their feelings for one another, they were starting a war alongside Edelgard. Who had time to fuck when your friends might die tomorrow? 

On the other hand… either of them could die tomorrow. And for the very short moment, it was a little less hectic. After five years of fighting with the Black Eagles Strike Force, their beloved Professor Byleth returned, and the tide of the war was almost immediately changed by her efforts.

She didn’t entirely trust Sylvain’s words, but she did trust his actions. She wanted him to show her.

Dorothea looked up at him from under her flashes, “It’s hard not to when you say such sweet things, darling.” Came her reply, and felt his other hand come to her waist in response. Sylvain inhaled slowly, taking in her perfume as his eyes never wavered from her face. 

Sylvain had been planning on asking her to dinner, but he didn’t think the look in her eyes right now signaled casual dinner date. He’d seen it before in her eyes, but had only ever gotten a taste of her. 

“Sylvain, would you like to come to my room?” 

His eyes darkened at the prospect, but he teased her, “And what would we be doing in your room, Dorothea?” 

She loved his games, her teeth worried her bottom lip as his deep voice made warmth rush down her spine. 

But two could play. She usually was coy while he direct so, 

“I’d like you to make love to me, Sylvain.” She lowered her voice but said it without breaking eye contact with him. She wanted to say more, but her words caught. They were too… exposed here. She had such trouble expressing herself openly. She had so much more she wanted to say, but couldn’t yet. 

He paused for a moment, exhaling before grabbing her hand, threading his fingers through hers. They didn’t say anything else, she just led him to her room. The same room she’d stayed in as a student so many years ago, but decorated much better now. 

As soon as the door was shut behind them, and the lock clicked into place, Sylvain crowded her against the door, one hand pressing to the mahogany above her head and the other coming to caress her cheek. 

She leaned into his touch, not unfamiliar but not completely familiar either. Especially not now. They weren’t the same people they were all those years ago. 

Sylvain tipped her chin up with a finger under it, looking into her eyes and making her telltale blush deepen. 

“You’re still blushing,” he murmured, eyes roaming across her beautiful face as his hand traveled down to find hers again, no longer needed under her chin as she couldn’t stop looking at him if she tried. 

“It means I like you, silly thing,” Dorothea whined, though her tone was mostly teasing. But it was true, Dorothea didn’t flush like this for just anybody. She had to care for her temperature to rise like this, for her beautiful features to flush a somewhat splotchy red. 

He smiled, “I’ve never seen you blush like that before.”

Dorothea was growing impatient, as his fingers that had threaded with hers again brought the back of her hand to his lips, instead of putting his lips legitimately anywhere else. 

“That’s because I’ve never felt like this about anyone before, darling.” 

A crease formed between his eyebrows and she frowned slightly, “What is it?” 

His eyes searched hers, “I’d like it if you’d call me Sylvain.” Both he and Dorothea had the habit of using pet names, both to distance themselves from their lovers emotionally and to ensure they did not mix up names. Darling. Sweets. Love. Silly thing. They were all said easier than a name, which could feel so intimate.

So she understood his meaning without him having to elaborate, “Sylvain….” she cooed softly and enjoyed watching a shiver go down his spine. 

And then, he finally kissed her. Dorothea’s free hand that wasn’t clutched in his, which was now held at his chest, slid up his torso, over his shoulder, and into his hair. 

Her name was said like a prayer on his lips as he kissed her gently, savoring her first. Dorothea sighed, content, as the way he said her name was delicious. She could feel his heart beating as he clutched her hand to his chest, his other hand falling from where it had been pressed against the door to slip around her waist. His heart was galloping, in a way she didn’t expect from Sylvain even with a near confession of love just moments before.

It filled her with warmth, all the way to the tips of her fingers and toes. She pulled her lips away gently, though his chased hers. She tugged his hand from his chest, to her own, to let him also feel how he effected her, how she felt about him. His confused expressed soon melted into understanding and, then, absolute adoration. 

Dorothea’s heart was pounding just as hard, and he pressed his forehead to hers.

“Your heart…” 

Is yours. She almost whispered, but held back. She wanted to so bad, but she…. well, that thought was best saved for after her current occupation. 

“Yours, too.” She said instead, craning her neck up to brush her nose against his affectionately. He sighed, his hand coming up to cup her cheek and he dove for her lips again. This time, it was not sweet and slow, but absolutely passionate. 

Dorothea had no trouble keeping up. She nipped at his lips as he pulled her backwards towards her bed. 

He sat at the edge of it, and was about to pull her into his lap when she stopped him. He watched as she kicked off her shoes and slipped her fingers under her skirt to find the waist of her stockings. She gently rolled them down her legs as Sylvain watched, then hiked her skirt high enough for him to get a glimpse of her smallclothes as she straddled his waist with bare legs. 

He had plucked off his gloves and slide bare hands up her legs as she settled in, her arms sliding over his shoulders. She rested her elbows there while both her hands went for his hair again, fussing with it affectionately as he started to press kisses to the underside of her jaw and down her throat. 

“Sylvain…” 

His hips canted up against her at the sound of his name, and Dorothea whined as his cock pressed against her through the leather of his pants. He liked that. Sylvain continued his path down her throat, though never sucking hard enough to leave a mark. His hands rested on her hips and pressed her down on him, grinding upwards and drawing another beautiful whine from her throat. 

He dragged his nose down, following his lips’ path and exhaling cool air on her dampened skin.

“Sylvain.” Much less patient now, demanding even. He chuckled against her throat and continued to grind against her, her manicured fingers dug into his scalp, her hands tugged at his hair causing delicious ache. 

“I like you like this, you’re such a needy princess, as usual.” He teased, and when he pulled back slightly he saw fire in her eyes. Oh? 

Her fingers tightened in his hair, tugging his mouth away from her neck as he tried to resume, and leveling him with her gaze. Dorothea trailed a finger down the side of his face as her other hand held him in place. A groan rumbled in his chest. 

“No longer a princess, then,” he conceded, his tongue darting out to lick his lips, “A Queen.” 

Pleased, Dorothea hummed in response and trailed her free hand down his chest and her other relaxed in his hair. She reached between them, feeling her hand brush against her own soaked smallclothes as she went for his pants. Clever fingers were into them quickly, and she had her hand around his cock in short order. 

“‘Thea,” Sylvain gasped, his hips canting into her hand. She pressed her lips to his jaw, admiring the lipstick mark she left... visible marks that could be quickly wiped away. When she so desperately wanted to mark him up and let him do it in return, where anyone could see. Love bites trailing from his ear to his cock, lipstick stains on all his collars, a bedroom to call theirs, all these things flashed before her eyes as she focused on the hitch of his breath and the heat of his body. 

Soon this wasn’t enough, and Sylvain nosed his way to his lips once more, an open mouthed, sloppy kiss that betrayed their desperation.

“Dorothea… My Queen,” he murmured, “Let me… I need to… get my head under your skirt.” 

How eloquent, but Dorothea could hardly blame him when she was flicking her wrist just right to make him keen. Impatient, Sylvain gripped her hips and she laughed as he got her under him. Her legs drew him closer as his hands went for her corset, opening it and sliding it out from under her. Then his hands took her hips again and grinned at her as he jerked her into a completely reclined position again. Her eyes flashed with want as she stared up at him.

His hands wasted no time in getting under her skirt, going for her smallclothes without breaking eye contact. 

“Hello, gorgeous.” He whispered, brushing his lips against hers before having to pull back and drag the clothes down her legs. One of them extended up to rest over his shoulder after it was freed from her underwear, which he prompted discarded onto the floor. 

Sylvain turned his head and pressed a kiss to her ankle, then her calf, then the back of her knee, which caused her to jerk. 

Soon he was sliding backwards down the bed, pressing a kiss to her knee, then her thigh, and as he went her fitted the other leg over his shoulder for good. Dorothea shook a little in anticipation, but trepidation flew from her mind as his teeth finally were introduced, nibbling up her leg. 

“Yes, please. Bite me. Mark me.” She sighed, not one for being shy about what she wanted from a lover. Rarely, if ever, though, had she ever allowed a partner to mark her. She hadn’t wanted it. She wasn’t theirs, didn’t want to be theirs. But Sylvain… she wanted to remember this for days after. She wanted to watch bite marks go from purple to red to yellow to pink. She wanted to press her fingers into hickeys and remember how he’d put it there.

“Are you sure?”

She nodded quickly, “Anywhere I can cover. I’ll wear long sleeves and stockings for weeks if I have to just….” She started babbling and it melted away into cry as Sylvain dug his teeth into her inner thigh. 

“Yes.” She urged him on as his tongue laved over the mark. She hiked her skirt up further, and his mouth followed. Higher and higher, he sucked and licked and bit and her cries rose in volume until she bit into the base of her thumb to keep quiet.

“One day, we’re going to have an entire wing of our estate to ourselves, and I’m going to make you scream.” Sylvain said casually, almost conversationally, as his eyes dragged up to hers. Oh, she very much was looking forward to that. And her heart galloped he said ‘our estate’. Not his, our. He was already imagining her in their life together. It honestly was hotter than anything else he could do or say. 

“One day, we’re going to take a trip to our summer home and I’m going to fuck you on every possible thing we own.” She responded, and she knew Sylvain liked the sound of that because he finally threw her other leg over his should and got his head under her skirt. 

His tongue worked through her folds, tasting her and groaning, one hand around her thigh gripping the supple flesh until Dorothea’s back arched. 

She panted, “I love your hands so much.” His nails flirted with her skin when he heard this. His lips closed around her clit and sucked gently, making her back arch again and her hand tug in his hair. Encouraged, he gave her no rest, and soon he fitted a finger inside her, two, three, and she was nearly drawing blood in her head trying to keep quiet, her teeth almost breaking skin on her thumb. 

“Sylvain, darling, I’m-”

He never slowed, and before she could even finish her sentence she was clenching around his fingers and crying out desperately. 

“Fuck, you beautiful man…” She panted as he continued at her through it, causing her to whine as her limbs twitched from sensitivity. 

When he finally emerged, his face was nearly dripping with her come, his fingers the same. Chest heaving, she caught his wrist and sucked his fingers into her mouth, her tongue twisting around his fingers. 

The look on his face was nearly reverant, “Oh, ‘Thea…” Next were his lips, which she kissed with no reservations. 

“You were so wonderful, love.” She praised him, sitting up with the support of his arms behind her back, “Do reminds me to return that particular favor in the future.” 

“Not a problem,” Sylvain agreed with his signature grin that made her heart do flip flops. She would very much look forward to getting on her knees for him, letting him come in her mouth, on her chest, wherever he liked…. 

But for now, she had a different plan.

She pressed against his chest, pushing him onto his back as she once against straddled his waist, but with both of them fully on the bed this time. She tugged his pants further down his legs and shivered, biting her lip, as the tip of his cock brushed against her folds as it sprung from his pants. 

He noticed, “Yeah?” He crooned at her, pressing his hips up and doing it again, slower, and Dorothea shuttered at the feeling. 

“Yeah? Tell me what you want.” He told her, goading her. Dorothea had just enough presence of mind to cast a quick, silent spell at her lower tummy, protection. As much as she… absolutely adored the idea of bearing Sylvain’s children, whom would be exceptionally beautiful as the result of their union. Literally gorgeous children, Hilda mentioned it drunk once. Dorothea couldn’t get the idea out of her head. 

But not now. The only thing she could think of that was sadder than her dying, was her dying pregnant with his child. 

That was the last rational thought she was able to muster before she cupped his face in her hands as he continued to tease her with his cock until she told him what she wanted. 

“I want to fuck you until you can’t make any more smart ass comments.” She cooed, smirking at him. He loved that. 

“Shut me up, my Queen.” 

She laughed, she couldn’t help it. It was just a little absurd, how comfortable she was with him. How he could tease her and make her cry out desperately one minute and the next be making her laugh. It was a connection she’d never experienced before. 

One of her hands went to his cock, pressed him against her opening, and slowly took him in. He was longer than he was thick, but it has still been a while for her. Her eyes closed as she enjoyed every inch of him, and when she was fully seated she wiggled her hips to get used to him. His hands trailed up her hips, her body still mostly obscured from him as she still wore her most of her clothes, just had shed the immediate barriers. Sylvain didn’t want to tempt himself with her throat and chest, he would want to mark her and it was much too visible. 

So instead, he told her what he was feeling, “One day, I’ll mark your neck so everyone knows.” It was like he was reading her mind. Dorothea couldn’t admit it aloud yet but the idea of having to hide marks and ultimately failing, everyone knowing who gave it to her…. who gave it to him… that was lovely. 

And she adores this… one day. It didn’t have to be today, but the promise of someday made her glow, made her start to rock her hips against his and making herself gasp. His hand slipped under her dress to touch her bare skin, hold her hips and let the calluses on his fingers make her shiver. 

“One day… we’ll make love completely bare, stay in bed all day… tire each other out and then nap in each others’ arms…” She crooned almost with a melody behind her voice, not that the words rhymed, the songstress came out. She never wanted to sing for lovers, never wanted to present herself as the beautiful entertainment to have on your arm, but she would sing for Sylvain.

Sylvain loved the sound of her voice, and what she was saying made him bite his lip as she rode him. 

“One day, I’ll spend hours exploring every inch of you in our bed.” Dorothea nodded along, closing her eyes as her legs started to shake. Sylvain’s strong hands on her hips started to pick up the slack, he sat up a little, bucked into her, caused her to moan and whine and cry out. Her hands braces herself pressed onto his chest, and she picked up the pace. Her thighs and abs burned deliciously as they chased their pleasure, and as they reached their peaks. This had been too drawn out for both of them, they were drowning in each other and it was sending them spiraling towards completion. 

He came first, calling her name like a prayer as he twitched inside of her. She loved the feeling of him coming inside of her, she found. He was the only man she’d ever allowed to. His fingers scrambled for her clit even as he came, determined to send her over the edge with him. It was just enough along with everything else, the look in his eyes, the way his hands felt on her skin, the pitch of his voice, the feel of his come filling her, she soon came with a desperate cry of his name. 

They shivered together as they rode it out, Dorothea gasping and murmuring sweet nothings in his ear as she collapsed on his chest. 

“Marvelous.” She finally said, sweetly pressing a kiss to the underside of his chin. His arms came around her, and she teetered to the side to lay half on top of him with his arm around her shoulders. They didn’t care about the mess, hey were just lost in each other now. 

They didn’t need to say anything, but Sylvain broke the silence after a while when he noticed her eyes seemed far away.

“Hey… where’d you go?” He whispered, and she quickly found her way back to him. She hesitated, before deciding to be honest with him about her insecurities. 

“I, That I don’t have… I mean. A Crest or any family background doesn’t bother you?” It was a question Dorothea admittedly already knew the answer to, but she needed to hear him say it in so many words. 

He gazed at her seriously, “I couldn’t care less. Really. Crests and lineage mean nothing to me. You mean everything to me.” 

Dorothea nodded, and snuggled in closer as he held her in his arms, “Thank you, Sylvain. I know it’s silly but… sometimes I need a little reassurance.” 

Sylvain tsked, “Your needs are not silly. I’m happy to provide.” He nosed his way across her cheek, nuzzling her temple before pressing a kiss there. 

Dorothea thought she knew what Sylvain needed to hear, too. It was hard for her to be completely vulnerable, exposed, but she wanted to try. 

“And, Sylvain?” 

He looked at her.

“I like you. I l-love you. If you wanted to abandon your title, I’d follow you. If all of our children are born without Crests, I don’t care. That’s not why I’m here.” 

His arms tightened around her, “I want Sylvain.” She whispered, to which he responded by nudging her chin up, and tenderly kissing her. 

“Marry me.” 

Dorothea froze then. No, she couldn’t. Not yet. This was perfect, and Dorothea intended to pursue this with everything in her, but…. there was something they had to do first.

“No, not yet.” 

Sylvain was surprised by her answer, and his face became guarded, “Oh.” 

Dorothea scrambles to explain as his eyes grew cloudy, he thought she was rejecting him. That everything she had said was just in the heat of the moment. He was pulling away. 

“Sylvain Gautier, you listen.” She whispered, frustrated as he didn’t slow down to think about what she was saying. His eyes refocused on her.

“I meant every word I said, don’t you dare doubt this.” Sylvain was silent and waiting for her to continue. 

“We…. have known each other almost entirely during war. Every day, I wonder if one of our friends is going to be killed. And I hate it.” 

“Even before, five years ago, we were barely… ourselves yet. We were children playing war in school, getting our kicks, trying to figure out where our paths led. And then we started an actual war, we’ve been fighting for five years and it’s only starting to come to an end because of Professor Byleth.” 

Dorothea took a deep breath, “I want to grow old with you Sylvain, but we can’t make that promise to each other right now, not when we might die tomorrow.” 

Tears filled her eyes, “And I couldn’t…. Bear to marry you and call you mine, only to lose you and be accused of being that gold digging peasant girl you just married during desperate wartimes. And I know it’s selfish but because even if it’s not true, it’s what they would think. I couldn’t bear the insult to your memory.” 

Dorothea drew him back to her, entangling their legs and feeling his arms tighten around her once more. 

“I want us to be closer now, tonight was an absolute dream and I will pursue it with everyone within me, but I want us to focus on winning this war. And living through this war. And…. when this is all over, I’d…” Her face suddenly felt hot, and she felt her flush creep down her face and onto her neck and chest. Sylvain found it so charming. He waited patiently for her to go on.

She struggled to continue, “I’d like to come home with you, and I’d like you to court me. Far away from this place of war and death, I want us to have the pleasantries we were denied as children entering war. I want us to have something that is ours, only ours. I want to know you.” 

Dorothea gave him credit for listening so long without interrupting. When she searched his eyes, she found resolution, determination, but no more betrayal. No more anger. He understood. 

And he would give her anything. 

So he asked, holding her face gently in his hands, “And then…. will you marry me, Dorothea?” 

She smiled softly, pressing her forehead against his, “What fun is knowing the ending before we even start?” She teased quietly.

But the kiss she pressed to his lips said, Yes.

**Author's Note:**

> Hope y’all enjoyed! This is unedited as of 7/27 but I plan to go back and make it flow a bit better and add some detail. 
> 
> SylvThea has such a special place in my heart. 
> 
> Part 2 will be set post-Crimson Flower and will show Dorothea and Sylvain getting to know each other post-war trauma. Yay. There will be more smut. Also Felix might show up.


End file.
